Distributed antenna systems and methods of wireless communications for facilitating simulcasting and de-simulcasting of downlink transmissions

ABSTRACT

Distributed antenna systems (DASs) can include a plurality of spatially separated remote antenna units. According to at least one example, a first group of remote antenna units can simulcast downlink transmissions on a first carrier with a particular sector identity (ID). A second group of remote antenna units, including at least one different remote antenna unit from the first group, can simulcast downlink transmissions on a second carrier with the same sector ID. According to at least one other example, two or more remote antenna units which include respective coverage areas that are non-adjacent to one another can be employed to simulcast downlink transmissions.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

The present Application for Patent claims priority to ProvisionalApplication No. 61/547,639 entitled “Base Station Modem Architecture forSimulcasting and De-Simulcasting in a Distributed Antenna System” filedOct. 14, 2011, and assigned to the assignee hereof and hereby expresslyincorporated by reference herein. The present Application for Patentalso claims priority to Provisional Application No. 61/576,836 entitled“Devices, Methods, and Systems for Simulcasting in Distributed AntennaSystems (DAS) to Improve Network Utilization” filed Dec. 16, 2011, andassigned to the assignee hereof and hereby expressly incorporated byreference herein.

TECHNICAL FIELD

Aspects of the present disclosure relate generally to wirelesscommunication systems, and more particularly, to simulcasting andde-simulcasting of transmissions in wireless communication systems.

BACKGROUND

In conventional wireless communication systems, base transceiverstations (BTS or base station) facilitate wireless communication betweenmobile units (e.g. access terminals) and an access network. A typicalbase station includes multiple transceiver units and antennas forsending radio signals to the mobile units (i.e., downlink transmissions)and for receiving radio signals from the mobile units (i.e., uplinktransmissions). Base stations are typically located so as tostrategically maximize communications coverage over large geographicalareas. Typically, the base stations are communicatively coupled to thetelephone network via backhaul connections.

As requirements for the reliability and the throughput of wirelesscommunication systems continue to increase, solutions and methods forproviding high data rate cellular access with high quality-of-serviceare desired. In some environments, a distributed antenna system (DAS)may be employed, where instead of covering an area by only one basestation, the same coverage is provided by multiple remote antenna units(RAU) controlled by a common base station. In other words, a distributedantenna system (DAS) is a network where spatially separated antennanodes or remote antenna units (RAUs) are connected to a common sourcevia a transport medium. A wireless communication system employing adistributed antenna system (DAS) may thus provide improved wirelessservice within a geographical area or structure. Some advantages of adistributed antenna system (DAS) architecture configuration include, forexample, improved reliability, reduced total power, possibility ofincreased capacity and more frequently occurring line-of-sight (LOS)condition between the remote antenna units (RAU) and the terminaldevice.

Although a distributed antenna system (DAS) architecture can provide anumber of benefits to a wireless communication system, the fullpotential for such distributed antenna systems (DAS) can be expanded byadditional features.

SUMMARY

One or more aspects of the present disclosure provide distributedantenna systems including simulcasting configurations adapted to improveperformance of a wireless communication system. In one or more examples,a distributed antenna system may include a plurality of remote antennaunits spatially separated from one another. A first group of remoteantenna units selected from the plurality of remote antenna units may beadapted to simulcast downlink transmissions with a particular sectoridentity (ID) on a first carrier. Furthermore, a second group of remoteantenna units may also be selected from the plurality of remote antennaunits, and may be adapted to simulcast downlink transmission with thesame sector ID on a second carrier different from the first carrier. Thesecond group may include at least one remote antenna unit that isdifferent from the remote antenna units of the first group.

In one or more further examples, a distributed antenna system mayinclude a plurality of remote antenna units spatially separated from oneanother. At least two remote antenna units with respective coverageareas that are non-adjacent to one another are adapted to simulcastdownlink transmissions.

Further aspects include methods for wireless communication and/ordistributed antenna systems including means for performing such methods.One or more examples of such methods may include simulcasting downlinktransmissions on a first carrier with a first group of two or moreremote antenna units employing a sector identity (ID). Downlinktransmissions may also be simulcast on a second carrier with a secondgroup of two or more remote antenna units employing the same sector ID,where at least one remote antenna unit of the second group differs fromthe remote antenna units of the first group.

In one or more additional examples of methods for wirelesscommunication, downlink transmissions may be simulcast with a firstremote antenna unit and with a second remote antenna unit such that thefirst remote antenna unit and the second remote antenna unit form asimulcasting group. The second remote antenna unit may be positioned sothat a coverage area associated with the second remote antenna unit isnot adjacent to a coverage area associated with the first remote antennaunit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a network environment accordingto at least one example in which one or more aspects of the presentdisclosure may find application.

FIG. 2 is a block diagram illustrating at least one example of staggeredsimulcasting distributions in a distributed antenna system where each ofthree different carriers is configured with a different simulcastingdistribution.

FIG. 3 is a flow diagram illustrating at least one example of a methodfor wireless communication.

FIG. 4 is a block diagram illustrating at least one example of adistributed antenna system architecture employable in a geographic areain which a population mass moves at least substantially as a group.

FIG. 5 is a flow diagram illustrating at least one example of a methodfor wireless communication.

FIG. 6 is a block diagram illustrating select components of a networkentity according to at least one example.

FIG. 7 is a simplified block diagram illustrating select components ofat least one example of a base station adapted to operate in conjunctionwith an RF connection matrix for implementing one or more of thefeatures described herein for a distributed antenna system (DAS).

FIG. 8 is a block diagram illustrating select details relating to atleast one example of the RF connection matrix of FIG. 7.

FIG. 9 is a block diagram illustrating select details relating to atleast one other example of an RF connection matrix of FIG. 7.

FIG. 10 is a flow diagram illustrating at least one example of a methodoperational on an RF connection matrix.

FIG. 11 is a block diagram illustrating a base station including anintegrated base station simulcast controller module according to atleast one example.

FIG. 12 is a block diagram illustrating additional details relating tothe base station of FIG. 11, which includes the integrated base stationsimulcast controller module according to at least one example.

FIG. 13 is a flow diagram illustrating at least one example of a methodoperational on a base station.

FIG. 14 is a block diagram illustrating select components of at leastone example of a distributed antenna system (DAS) employing a basestation simulcast controller module implemented as a processing systemadapted to communicate with a plurality of base stations.

FIG. 15 is a flow diagram illustrating at least one example of a methodoperational on a base station simulcast controller module.

DETAILED DESCRIPTION

The following description set forth below in connection with theappended drawings is intended as a description of various configurationsand is not intended to represent the only configurations in which theconcepts described herein may be practiced. The following descriptionincludes specific details for the purpose of providing a thoroughunderstanding of various concepts. However, it will be apparent to thoseskilled in the art that these concepts may be practiced without thesespecific details. In some instances, well known circuits, structures,techniques and components are shown in block diagram form in order toavoid obscuring such concepts.

In the following description, certain terminology is used to describecertain features. For example, the term “base station” and “accessterminal” are used herein, and are meant to be interpreted broadly. Forexample, a “base station” refers generally to a device that facilitateswireless connectivity (e.g., for one or more access terminals) to acommunication or data network. A base station may be capable ofinterfacing with one or more remote antenna units. A base station mayalso be referred to by those skilled in the art as an access point, abase transceiver stations (BTS), a radio base station, a radiotransceiver, a transceiver function, a basic service set (BSS), anextended service set (ESS), a Node B, an eNode B, a femto cell, a picocell, or some other suitable terminology.

An “access terminal” refers generally to one or more devices thatcommunicate with one or more other devices through wireless signals.Examples of access terminals include mobile phones, pagers, wirelessmodems, personal digital assistants, personal information managers(PIMs), personal media players, palmtop computers, laptop computers,tablet computers, televisions, appliances, e-readers, digital videorecorders (DVRs), machine-to-machine (M2M) enabled devices, and/or othercommunication/computing devices which communicate, at least partially,through a wireless or cellular network.

FIG. 1 is a block diagram illustrating a network environment in whichone or more aspects of the present disclosure may find application. Thewireless communication system 100 is implemented with a distributedantenna system (DAS) architecture and may be configured according to oneor more conventional telecommunication system, network architecture,and/or communication standard. By way of example and not limitation, thewireless communication system 100 may be configured according to one ormore of Evolution Data Optimized (EV-DO), Universal MobileTelecommunication Systems (UMTS), Long Term Evolution (LTE) (in FDD,TDD, or both modes), LTE-Advanced (LTE-A) (in FDD, TDD, or both modes),CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16(WiMAX), IEEE 802.20, Ultra-Wideband (UWB), Bluetooth, and/or othersuitable systems. The actual telecommunication system, networkarchitecture, and/or communication standard employed will depend on thespecific application and the overall design constraints imposed on thesystem 100.

The wireless communication system 100 generally includes a plurality ofremote antenna units (RAUs) 102, one or more base stations 104, a basestation controller (BSC) 106, and a core network 108 providing access toa public switched telephone network (PSTN) (e.g., via a mobile switchingcenter/visitor location register (MSC/VLR)) and/or to an IP network(e.g., via a packet data switching node (PDSN)). The system 100 cansupport operation on multiple carriers (waveform signals of differentfrequencies). Multi-carrier transmitters can transmit modulated signalssimultaneously on the multiple carriers. Each modulated signal may be aCDMA signal, a TDMA signal, an OFDMA signal, a Single Carrier FrequencyDivision Multiple Access (SC-FDMA) signal, etc. Each modulated signalmay be sent on a different carrier and may carry control information(e.g., pilot signals), overhead information, data, etc.

The remote antenna units 102, which are identified as 102-a, 102-b and102-c, are adapted to wirelessly communicate with one or more accessterminals 110. As illustrated, each of the remote antenna units 102-a,102-b, 102-c are spatially separated from each other and are connectedto a common base station 104 via a transport medium 112. The transportmedium 112 may include a fiber cable and/or an optical cable in variousexamples. Accordingly, the base station 104 can actively distributesignals to the plurality of remote antenna units 102-a, 102-b, 102-c forcommunicating with the one or more access terminals 110.

The base station 104 can be configured to communicate with the accessterminals 110 by means of the remote antenna units 102-a, 102-b, 102-cand under the control of the base station controller 106 via a pluralityof carriers. The base station 104 can provide communication coverage fora respective geographic area, referred to herein as a cell. The cell canbe divided into sectors 114 formed by the respective coverage area ofeach remote antenna unit 102-a, 102-b, 102-c, as shown by correspondingsectors 114-a, 114-b and 114-c.

In at least some examples, a base station 104 can be adapted to employtwo or more of the remote antenna units 102-a, 102-b, 102-c to transmitessentially the same signal, potentially to be received at a singleaccess terminal 110. This type of transmission is typically referred toas simulcasting. For example, the base station 104 may transmit adownlink signal from the two remote antenna units 102-a and 102-b.Simulcasting can improve the signal to interference and noise ratio(SINR) at the receiving access terminal 110, since the signal from eachremote antenna unit 102-a, 102-b ideally adds together constructively atthe receiving access terminal 110. Additionally, it is less likely thatall the simulcasted transmissions will be blocked due to geography orfading than it might be for a transmission from a single remote antennaunit 102. In the case where remote antenna units 102-a and 102-bsimulcast a downlink signal, the two areas depicted by sectors 114-a and114-b can become a single sector and may employ a single sector identity(e.g., a single pseudo-random noise (PN) code).

The base station 104 can also be adapted to transmit different signalsfrom different remote antenna units 102-a, 102-b, 102-c. This type oftransmission is typically referred to as de-simulcasting. For example,the base station 104 may be adapted to transmit a different downlinksignal from the remote antenna unit 102-c. De-simulcasting can beperformed using the same carrier frequency as the one used by the otherremote antenna units 102-a, 102-b, or using a different carrierfrequency. De-simulcasting can improve the capacity of the wirelesscommunication system 100 by increasing the data rate per unit area. Thatis, when each remote antenna unit 102-a, 102-b, 102-c serving aparticular geographic area is transmitting a different signal, a greaternumber of access terminals 110 may be served by the system 100. In thecase where a remote antenna unit 102-a, 102-b, 102-c is adapted tode-simulcast downlink signals, each area 114-a, 114-b, 114-c employs anindividual and separate sector ID.

As noted above, a plurality of remote antenna units can be adapted tosimulcast downlink transmissions, where each group of simulcastingremote antenna units forms a sector. As used herein, a plurality ofsimulcasting remote antenna units can form a sector by employing acommon sector identity, such as a common pseudo-random noise (PN) code.FIG. 2 is a block diagram illustrating a coverage area 200 including aplurality of remote antenna units (such as the remote antenna units102-a, 102-b, 102-c of FIG. 1) acting in groups to simulcast downlinktransmissions. As depicted, each hexagon represents a coverage areaassociated with one remote antenna unit for transmitting and receivingradio signals. In addition, each remote antenna unit (i.e., eachhexagon) is associated with one or more other remote antenna units(i.e., one or more other hexagons) forming a group for simulcastingdownlink transmissions. Each simulcasting group of two or more remoteantenna units can employ a common sector ID to form a single sector. Inthe examples depicted by FIG. 2, the coverage area 200 is configuredwith nineteen (19) different simulcasting groups (e.g., sectors Athrough S each depicted with unique hatch patterns), where eachsimulcasting group includes three (3) remote antenna units.

According to a feature of the present disclosure, the coverage area 200can be configured to employ different simulcasting group configurationsfor each of a plurality of different carriers (e.g., different waveformsignals of different frequencies). In other words, the remote antennaunits employed for simulcasting downlink transmissions with a particularsector ID for a first carrier can differ from the remote antenna unitsemployed for simulcasting downlink transmissions with the same sector IDfor a second carrier. This feature can be further understood byreference to the non-limiting example depicted by the three differentdiagrams shown in FIG. 2.

The top diagram in FIG. 2 shows the simulcasting group distribution fora first carrier in the coverage area 200. As illustrated, the remoteantenna units are grouped into nineteen (19) different simulcastinggroups, where each group employs a different sector ID (e.g., sector IDsA-S). Each group includes three (3) different remote antenna units, andsimulcasts downlink transmissions for the first carrier using a commonsector ID. For example, the remote antenna units forming the groupadapted to simulcast downlink transmissions with the sector ID ‘A’ forthe first carrier are shown to include the middle three (3) remoteantenna units depicted without any hatch pattern and indicated by arrow202. Similarly, the remote antenna units forming the group adapted tosimulcast downlink transmission with the sector ID ‘P’ for the firstcarrier are shown to include the three (3) remote antenna units locatedat the top and middle of the coverage area 200, and are depicted with ahatch pattern of vertical lines and indicated by arrow 204.

In the middle diagram of FIG. 2, the simulcasting group distribution fora second carrier is shown for the same coverage area 200. In thisexample, the same nineteen (19) different sector IDs are employed (e.g.,sector IDs A-S). However, for the second carrier, each simulcastinggroup (e.g., each sector ID) employs a different group of three (3)remote antenna units for simulcasting downlink transmissions. Forinstance, in the example depicted by FIG. 2, the remote antenna unitsforming the group adapted to simulcast downlink transmissions with thesector ID ‘A’ (indicated by arrow 206) for the second carrier are shownto include two (2) remote antenna units that differ from the remoteantenna units employed for simulcasting with the same sector ID ‘A’ forthe first carrier. In this example, each of the simulcasting groups isshifted up and to the right.

For some simulcasting groups with the second carrier, the remote antennaunits are separated so that the three (3) remote antenna units of asimulcasting group are no longer adjacent to one another like they werefor the first carrier. For instance, the group of remote antenna unitsemployed for simulcasting downlink transmissions with the sector ID ‘P’for the second carrier are shown to include one (1) remote antenna unit208 at the top and middle of the coverage area 200, and two (2) otherremote antenna units 210 at the bottom left side of the coverage area200.

The bottom diagram of FIG. 2 illustrates the simulcasting groupdistribution for a third carrier for the same coverage area 200. In thisexample, the same nineteen (19) different sector IDs are employed (e.g.,sector IDs A-S). However, for the third carrier, each simulcasting group(e.g., each sector ID) employs yet another different group of three (3)remote antenna units for simulcasting downlink transmissions. Forinstance, in the example depicted by FIG. 2, the remote antenna unitsforming the group adapted to simulcast downlink transmissions with thesector ID ‘A’ (indicated by arrow 212) for the third carrier are shownto include two (2) remote antenna units that differ from the remoteantenna units employed for simulcasting with the same sector ID for thefirst or second carriers. In this example, each of the simulcastinggroups is shifted up and to the left.

As with the middle diagram, the bottom diagram includes somesimulcasting groups including remote antenna units that are spatiallyseparated and no longer adjacent to one another. For example, the groupof remote antenna units employed for simulcasting downlink transmissionswith the sector ID ‘P’ for the third carrier are shown to include one(1) remote antenna unit 214 at the top and center of the coverage area200, one (1) remote antenna unit 216 at the lower left side of thecoverage area 200, and one (1) remote antenna unit 218 at the lowerright side of the coverage area 200.

In the illustrated example, where the simulcasting configurations have a3:1 ratio (i.e., three (3) remote antenna units to one (1) sector), asignificant improvement in the signal to interference and noise ratio(SINR) can be achieved by providing different simulcasting groupdistributions for different carriers. For instance, a conventionaldistributed antenna system (DAS) would employ only one of the threesimulcasting group distribution configurations of FIG. 2 for all threecarriers. That is, a conventional distributed antenna system (DAS) wouldtypically use either the top, middle or bottom configuration for allthree carriers, and would achieve some improvement to signal tointerference and noise ratio (SINR) for access terminals distributedthrough the coverage area 200. By comparison, employing the simulcastingarchitecture where a different simulcasting group distribution isemployed for each carrier according to the configurations describedabove, the signal to interference and noise ratio (SINR) can be furtherimproved. By way of example and not limitation, a four (4) dBimprovement was determined in the described configurations in the 10%tail for single-carrier access terminals which are uniformly droppedover the geography, when they are assigned to the carrier which has thebest simulcasting pattern for the particular location of the accessterminal.

In addition, an overall gain in network throughput can also be obtainedby employing the three different simulcasting group distributions ofFIG. 2 as compared to employing the same simulcasting group distributionfor all carriers. In the described configurations, more time can beallocated on the simulcasting distribution which is best for each user,resulting in an overall gain in the network throughput as well as anincrease in the 10% tail throughput. By way of example and notlimitation, an increase in the overall network throughput as well as anincrease in the 10% tail throughput of 27% was determined in theparticular example shown in FIG. 2. However, smaller or largerthroughput gains may be possible, depending on the specific deploymentmodel implemented.

It is noted that the number of carriers and the simulcastingdistribution configurations described above with reference to FIG. 2 areonly examples, and that other configurations and other numbers ofcarriers may be employed according to various implementations of theunderlying features.

At least one aspect of the present disclosure includes methods forwireless communication. FIG. 3 is a flow diagram illustrating at leastone example of a method 300 for wireless communication associated withthe features described above with reference to FIG. 2. The method 300includes simulcasting downlink transmissions on a first carrier with afirst group of two or more remote antenna units employing a commonsector ID at step 302. At step 304, downlink transmissions are simulcaston a second carrier with a second group of two or more remote antennaunits employing the same sector ID. At least one remote antenna unit ofthe second group differs from the remote antenna units making up thefirst group.

For example, the group 202 in FIG. 2 may be a first group of remoteantenna units simulcasting downlink transmissions with the sector ID ‘A’on the first carrier, and the group 206 may be the second group ofremote antenna units simulcasting downlink transmission with the samesector ID ‘A’ on the second carrier. In the example, the remote antennaunits making up the group 202 are different from the remote antennaunits making up the group 206. That is, two of the remote antenna unitsof the second group 206 are different remote antenna units from theremote antenna units making up the first group 202. In this non-limitingexample, one of the remote antenna units in the first group 202 is alsoincluded as a remote antenna unit of the second group 206.

At least some features of the present disclosure relate to increasingefficiency by strategically distributing resources in a coverage area.Typically, strategies for increasing the spectral efficiency for aparticular area have included increasing the number of base stationsectors in that area by an increase in the number of base stations,which base stations can be fairly expensive. In some instances, however,all locations within the particular coverage area may not need increasedspectral efficiency at the same time. It has been determined that massesof people may tend to move together, so that increased spectralefficiency would be beneficial at only one portion of a given area foreach moment in time. For example, FIG. 4 is a block diagram illustratinga geographic coverage area 400 where a majority of the population may befound in and around the area 402 during one part of each day and/orweek, and in and around the area 404 during another part of each dayand/or week. For instance, a majority of the population within thecoverage area 400 may move into the area 402 in the mornings as thepopulation goes to work, and then may be found generally in the area 404in the evenings as the population returns to their homes.

According to a feature, simulcasting distribution configurations may beimplemented for increased efficiency in distributing resources within acoverage area. For instance, a simulcasting distribution configurationmay be implemented in a manner to increase spectral efficiency byincreasing the number of sectors in a given part of the coverage area,without increasing the number of base stations.

Referring still to FIG. 4, a plurality of remote antenna units 102 arespatially distributed throughout the coverage area 400. In theillustrated example, simulcasting groups are formed with remote antennaunits that are geographically separated such that the respectivecoverage areas of the remote antenna units forming a simulcasting groupare generally not adjacent to one another. In general, the geographicseparation between simulcasting remote antenna units may be such that anaccess terminal communicating with at least one remote antenna unit of asimulcasting group is not able communicate with at least one otherremote antenna unit of the same simulcasting group at any given time.

Each simulcasting group is depicted in FIG. 4 with a letter indicating asector ID with which the remote antenna units are configured tosimulcast downlink transmissions. For example, the two remote antennaunits 102A are depicted with the letter ‘A’ to indicate that these tworemote antenna units are adapted to simulcast transmissions using thesame sector ID ‘A’. Similarly, the two remote antenna units 102E aredepicted with the letter ‘E’ to indicate that these two remote antennaunits simulcast transmissions using the same sector ID ‘E’. As shown,the two remote antenna units 102A are geographically separated such thatthe respective coverage areas of each remote antenna unit 102A are notadjacent. The two remote antenna units 102E are likewise geographicallyseparated. Similar simulcasting pairs are also shown for sector IDs ‘B’through ‘D’ and ‘F’ through ‘I’, with the remote antenna units for eachpair being geographically separated from one another.

In the illustrated example, wherever there is a mass of usersconcentrated in a given area (e.g., 402 or 404), those users are servedby multiple sectors. For instance, when a large majority of thepopulation is found in and around the area 402 (e.g., in the morning),they will be served generally by all of the sectors ‘A’-‘I’. When themajority of the population moves to an area in and around the area 404(e.g., in the evening), they will be served generally by the same numberof sectors ‘A’-‘I’. As the population moves throughout the network in alarge majority, there is a low probability all remote antenna units willexperience large throughput demands. Therefore, with the simulcastingpattern shown in FIG. 4, the population mass will typically be served byeight (8) or nine (9) different sectors as the population moves at leastsubstantially together throughout the network. This is about twice asmany sectors as would be available in a typical configuration wheresimulcasting remote antenna units would be geographically adjacent toone another. In addition, the number of sectors per area is increasedwithout increasing the number of base stations serving that area.Furthermore, if the same population becomes less concentrated andspreads more evenly throughout the coverage area 400, the sectors‘A’-‘I’ employed for serving the entire coverage area 400 across thedistributed simulcasting pattern of remote antenna units 102 is stillsufficient to meet the population's demand.

It is noted that in some implementations not all the remote antennaunits within a particular coverage area 400 may be adapted to simulcast.Instead, there may be a combination of simulcasting remote antenna unitsand de-simulcasting remote antenna units, according to numerous possibleconfigurations.

At least one aspect of the present disclosure includes methods forwireless communication. FIG. 5 is a flow diagram illustrating at leastone example of a method 500 for wireless communication associated withthe features described above with reference to FIG. 4. The method 500includes simulcasting downlink transmissions with a first remote antennaunit at step 502. At step 504, the downlink transmissions are alsosimulcast with a second remote antenna unit, such that the first remoteantenna unit and the second remote antenna unit form a simulcastinggroup. The second remote antenna unit is located so that a coverage areaassociated with the second remote antenna unit is not adjacent to acoverage area associated with the first remote antenna unit.

For example, the plurality of remote antenna units identified byreference number 102A in FIG. 4 may simulcast downlink transmissions. Asdepicted, the coverage area (depicted by each respective hexagon) of thetwo remote antenna units 102A are not adjacent to each other.

According to at least one feature, the simulcasting distributionconfigurations and associated methods for wireless communicationsdescribed above with reference to FIGS. 2-5 may be dynamicallyconfigured. In some instances, the network (e.g., a base station, a basestation controller, etc.) can measure one or more parameters (e.g., theinterference, traffic demand statistics, etc.) and determine how toarrange the simulcasting group configurations across the geography andacross carriers to increase stability and throughput to each user, aswell as to the network as a whole. For example, at least one remoteantenna unit in a simulcasting group can be changed in response to oneor more network traffic parameters. That is, one or more remote antennaunits can be added to and/or removed from a simulcasting group inresponse to at least one network traffic parameter.

For instance, it may occur that access terminals operating within acoverage area are not dispersed uniformly through the area. For example,it may be determined by the network that access terminals in a specificregion are especially active at a particular time along one or morehandoff boundaries (e.g., along a region between simulcasting groups ‘C’and ‘P’ in the top diagram of FIG. 2). In such an instance, it may bebeneficial to dynamically change the simulcasting group distributions.For example, the simulcasting group distributions may be dynamicallymodified by the network to employ a simulcasting group distribution thatoptimizes the throughput and capacity for those access terminals. In theexample from FIG. 2, for instance, it may be beneficial to dynamicallychange the group distributions so that two of the carriers or even allthree carriers employ the same simulcasting group distributiondetermined to optimize the throughput and capacity for those accessterminals located along the one or more handoff boundaries indicatedabove. That is, the network may change at least one remote antenna unitin any of the different groups for any of the different carrierconfigurations. When the network dynamics return to a more uniformlydispersed access terminal distribution, the simulcasting distributionconfiguration can return to the three configurations depicted in FIG. 2,or some other configurations.

In the example of FIG. 4, the network may be adapted to identify themovement of the mobile population and responsively adapt thesimulcasting group configurations to accommodate the population mass.For instance, the network may identify a large concentration of accessterminals in a particular area. For example, there may be a sportingcontest, concert, or other spectacle scheduled at a specific venue,causing the population to move generally together as a group andconcentrate in and around that venue. The network may identify thismovement in the population and may deploy a simulcasting groupconfiguration similar to the configuration depicted by FIG. 4 in orderto increase a number of sectors available for the area around the venuein order to improve network performance for the concentrated population.That is, the network can change which remote antenna units simulcast by,for example, adding one or more remote antenna units to and/or removingone or more remote antenna units from a simulcasting group in responseto at least one network traffic parameter.

The various features, simulcasting configurations and methods forwireless communication described above can be implemented by one or morenetwork entities. Such one or more network entities may be generallyimplemented with one or more processing systems. FIG. 6 is a blockdiagram illustrating select components of a processing system 600according to at least one example. The processing system 600 maygenerally include a processing circuit 602 coupled to a communicationsinterface 604 and to a storage medium 606. In at least some examples,the processing circuit 602 may be coupled to the communicationsinterface 604 and the storage medium 606 with a bus architecture,represented generally by the bus 608. The bus 608 may also link variousother circuits such as timing sources, peripherals, voltage regulators,and power management circuits, which are well known in the art, andtherefore, will not be described any further.

The processing circuit 602 is arranged to obtain, process, and/or senddata, control data access and storage, issue commands, and control otherdesired operations. The processing circuit 602 may include circuitryconfigured to implement desired programming provided by appropriatemedia in at least one embodiment. For example, the processing circuit602 may be implemented as one or more of a processor, a controller, aplurality of processors and/or other structure configured to executeexecutable instructions including, for example, software and/or firmwareinstructions, and/or hardware circuitry. Examples of the processingcircuit 602 may include a general purpose processor, a digital signalprocessor (DSP), an application specific integrated circuit (ASIC), afield programmable gate array (FPGA) or other programmable logiccomponent, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general purpose processor may be a microprocessorbut, in the alternative, the processor may be any conventionalprocessor, controller, microcontroller, or state machine. A processormay also be implemented as a combination of computing components, suchas a combination of a DSP and a microprocessor, a number ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. These examples of the processingcircuit 602 are for illustration and other suitable configurationswithin the scope of the present disclosure are also contemplated.

The processing circuit 602 is adapted for processing, including theexecution of programming, which may be stored on the storage medium 606.As used herein, the term “programming” shall be construed broadly toinclude without limitation instructions, instruction sets, code, codesegments, program code, programs, subprograms, software modules,applications, software applications, software packages, routines,subroutines, objects, executables, threads of execution, procedures,functions, etc., whether referred to as software, firmware, middleware,microcode, hardware description language, or otherwise.

The communications interface 604 is configured to facilitate wiredand/or wireless communications of the processing system 600. Forexample, the communications interface 604 may include circuitry and/orprogramming adapted to facilitate the communication of informationbi-directionally with respect to one or more other processing systems.In instances where the communications interface 604 is configured tofacilitate wireless communications, the communications interface 604 maybe coupled to one or more antennas (not shown), and may includeswireless transceiver circuitry, including at least one receiver circuit610 (e.g., one or more receiver chains) and/or at least one transmittercircuit 612 (e.g., one or more transmitter chains).

The storage medium 606 may represent one or more devices for storingprogramming and/or data, such as processor executable code orinstructions (e.g., software, firmware), electronic data, databases, orother digital information. The storage medium 606 may also be used forstoring data that is manipulated by the processing circuit 602 whenexecuting programming The storage medium 606 may be any available mediathat can be accessed by a general purpose or special purpose processor.By way of example and not limitation, the storage medium 606 may includea non-transitory computer-readable medium such as a magnetic storagedevice (e.g., hard disk, floppy disk, magnetic strip), an opticalstorage medium (e.g., compact disk (CD), digital versatile disk (DVD)),a smart card, a flash memory device (e.g., card, stick, key drive),random access memory (RAM), read only memory (ROM), programmable ROM(PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), aregister, a removable disk, and/or other non-transitorycomputer-readable mediums for storing information, as well as anycombination thereof. The storage medium 606 may be coupled to, or atleast accessible by the processing circuit 602 such that the processingcircuit 602 can read information from, and write information to, thestorage medium 606. For instance, the storage medium 606 may be residentin the processing system 600, external to the processing system 600, ordistributed across multiple entities including the processing system600. In some examples, the storage medium 606 may be integral to theprocessing circuit 602.

Programming stored by the storage medium 606, when executed by theprocessing circuit 602, causes the processing circuit 602 to perform oneor more of the various functions and/or process steps described herein.The storage medium 606 may include simulcasting group distributionoperations (i.e., instructions) 614. The simulcasting group distributionoperations 614 can be implemented by the processing circuit 602. Thus,according to one or more aspects of the present disclosure, theprocessing circuit 602 may be adapted to perform any or all of theprocesses, functions, steps and/or routines for any or all of thenetwork entities (e.g., base station 104, 702, 1102; base stationcontroller 106, 708, 1106; RF connection matrix 704; base stationsimulcast controller module 1114, 1402 etc.) described herein. As usedherein, the term “adapted” in relation to the processing circuit 602 mayrefer to the processing circuit 602 being one or more of configured,employed, implemented, or programmed to perform a particular process,function, step and/or routine according to various features describedherein.

In at least one example, a processing system 600 may be implemented asan RF connection matrix, which may also be referred to as a “head end”,and/or as a base station coupled with such an RF connection matrix. Sucha processing system 600 can be adapted to facilitate simulcastingaccording to one or more of the features described herein, such as thosedescribed above with reference to FIGS. 2-5. FIG. 7 is a simplifiedblock diagram illustrating select components of a base station 702adapted to operate in conjunction with an RF connection matrix 704 forimplementing one or more of the features described herein for adistributed antenna system (DAS).

As shown, a base station (BS) 702 is utilized to enable multiple accesswireless communication. The base station 702 includes a backhaulinterface 706 for backhaul communication with a base station controller(BSC) 708. Further, the base station 702 includes a base station modemblock 710 including a plurality of base station sector controllers 712A,712B, and 712C, and a corresponding plurality of base station antennaports 714A, 714B, and 714C. Within the base station modem block 710, therespective base station sector controllers 712A, 712B, and 712C eachinclude circuitry for transmitting a downlink and receiving an uplinkfor one sector or cell in the wireless communication system. In oneexample, all of the base station sector controllers 712A, 712B, and 712Cmay reside on the same channel card. In another example, they may be ondifferent channel cards. The base station antenna ports 714A, 714B, and714C are each coupled to an RF connection matrix 704.

In this example, the RF connection matrix 704 determines how theoutgoing signals are routed from the base station 702 to a plurality ofremote antenna units 716 for downlink transmission. Typically, thecoupling between the base station antenna ports 714 and the RFconnection matrix 704 is made by way of respective RF electricalcommunication interfaces. The RF connection matrix 704 is coupled to aplurality of remote antenna units 716 (e.g., 716A, 716B, 716C, 716D, and716E). In at least some implementations, the coupling between the RFconnection matrix 704 and the remote antenna units 716 includesrespective transport medium interfaces 718A, 718B, 718C, 718D, and 718E.Each of the base station antenna ports 714A, 714B, 714C may include oneor more antenna ports to facilitate coupling a respective base stationsector with one remote antenna unit 716 or with a plurality of remoteantenna units 716.

The distributed antenna system (DAS) illustrated in FIG. 7 may beutilized for simulcasting and de-simulcasting any of a plurality ofconfigurations including configurations according to the generalprinciples described above. For example, the remote antenna units 716Aand 716B may be simulcast, the remote antenna units 716C and 716D may besimulcast, and the remote antenna unit 716E may be de-simulcast.Furthermore, the depicted grouping can be implemented for one carrier,while other carriers may employ different grouping configurations.

The RF connection matrix 704 may employ various configurations, such asone of the configurations depicted in FIGS. 8 and 9. Referring initiallyto FIG. 8, a block diagram is shown illustrating select details relatingto at least one example of an RF connection matrix. The example depictedin FIG. 8 can be employed for various simulcasting configurations wherea plurality of remote antenna units 716 are employed for simulcastingdownlink transmissions. By way of example and not limitation, the RFconnection matrix 704A may be employed for implementing one or more ofthe features described herein with reference to FIG. 4.

In FIG. 8, the three base station sector controllers 712A, 712B, and712C are shown. Here, the base station sector controllers 712A, 712B,and 712C are coupled, by way of a backhaul connection 706, to the basestation controller 708. Further, the base station controller 708 iscoupled to a network such as the Internet 802. Although the base stationantenna ports 714 are not illustrated in FIG. 8, the interface betweenthe base station sector controllers 712A, 712B, and 712C and the RFconnection matrix 704A is assumed to include such antenna ports.

The RF connection matrix 704A is provisioned to route the outgoingsignals from the base station sectors 712A, 712B, 712C to the remoteantenna units 716 for downlink transmission. Here, the RF connectionmatrix 704A includes an electrical portion where electrical RF signalsoutput by the base station sectors 712 are provided to a central hub 804having optical-electrical interfaces (0/E) for coupling the electricalRF signals with optical fibers 806 for transmission to the remoteantenna units 716 as optical signals in an optical portion. The opticalsignals are then converted back to electrical signals atelectrical-optical interfaces (E/O) 808 for interfacing directly withantennas. Here, the E/O and various active elements are illustrated atthe remote antenna units 716. However, in various examples all or someportion of these components may be located outside the remote antennaunits 716.

In the illustrated example, the RF connection matrix 704A is provisionedto simulcast the downlink signal from the first base station sector 712Afrom the first two remote antenna units 716A and 716B. As an example,simulcasting can be accomplished by way of RF combining in theelectrical portion of the RF connection matrix 704A, as depicted at 810.That is, the electrical signal representing a downlink transmission sentfrom the first base station sector 712A is split and fed to two O/Einterfaces at the central hub 804, so that corresponding optical signalsare transmitted over the first and second fibers 806A and 806B to thefirst and second remote antenna units 716A and 716B to be simulcasted.

Further, the RF connection matrix 704A is provisioned to simulcast thedownlink signal from the second base station sector 712B from the thirdand fourth remote antenna units 716C and 716D. As another example,simulcasting can be accomplished by way of fiber combining in theoptical portion of the RF connection matrix 704A, as depicted at 806C.That is, the electrical signal representing a downlink transmission sentfrom the second base station sector 712B is fed into an O/E interface atthe central hub 804, after which the corresponding optical signal issplit from one to two fibers 806C, so that the corresponding opticalsignals are sent to the third and fourth remote antenna units 716C and716D to be simulcasted.

Still further, the RF connection matrix 704A is provisioned tode-simulcast the downlink signal from the third base station sector 712Cfrom the fifth remote antenna unit 716E. That is, the electrical signalrepresenting a downlink transmission sent from the third base stationsector 712C is fed into an O/E interface at the central hub 804, afterwhich the corresponding optical signal is sent to the fifth remoteantenna unit 716E to be transmitted.

Turning to FIG. 9, a block diagram is shown illustrating select detailsrelating to at least one other example of an RF connection matrix. Theexample depicted in FIG. 9 can be employed for various simulcastingconfigurations where a plurality of remote antenna units 716 areemployed for simulcasting downlink transmissions, as well as forimplementing different simulcasting configurations among two or moredifferent carriers. By way of example and not limitation, an RFconnection matrix 704B depicted in FIG. 9 may be employed forimplementing one or more of the features described above with referenceto FIGS. 2 and 4.

In FIG. 9, the three base station sector controllers 712A, 712B, and712C are once again depicted with the base station sector controllers712A, 712B, and 712C coupled by way of a backhaul connection 706 to thebase station controller 708. Further, the base station controller 708 iscoupled to a network such as the Internet 902. Although the base stationantenna ports 714 from FIG. 7 are not illustrated in FIG. 9, theinterface between the base station sector controllers 712A, 712B, and712C and the RF connection matrix 704B (e.g., the carrier separationfilters 904) is assumed to include such base station antenna ports 714in FIG. 7.

The RF connection matrix 704B is provisioned to route the outgoingsignals from the base station sector controllers 712A, 712B, 712C to theremote antenna units 716 for downlink transmission. In the example ofFIG. 9, the RF connection matrix 704B includes a plurality ofcarrier-specific RF connection matrix modules 906. Each of therespective carrier-specific RF connection matrix modules 906 can routethe carrier-specific downlink transmissions to one or more remoteantenna units 716 for transmission on the respective carrier.

The RF connection matrix 704B can include a carrier separation filter904 coupled with the antenna ports for each base station sectorcontroller 712. For instance, respective carrier separation filters904A, 904B, and 904C are coupled with the base station sectorcontrollers 712A, 712B, and 712C. Each of the carrier separation filtersis further coupled with the plurality of carrier-specific RF connectionmatrix modules 906. The carrier separation filters 904 are adapted toreceive one or more signals associated with a sector identity (ID),where the one or more signals include downlink transmissions for aplurality of carriers. For instance, a carrier separation filter 904 mayreceive one or more signals from one or more base station sectorcontrollers 712. The carrier separation filters 904 then separate thedownlink transmissions for each carrier and provide these downlinktransmissions to a respective carrier-specific RF connection matrixmodule 906.

In some examples, the carrier-specific RF connection matrix modules 906may provide the carrier-specific downlink transmissions to a carriercombine filter 908 associated with a respective remote antenna unit 716.For instance, the carrier combine filters 908A, 908B, and 908C arerespectively associated with remote antenna units 716A, 716B, and 716C.The carrier combine filters 908 can receive from each of thecarrier-specific RF connection matrix modules 906 the downlinktransmissions intended for the associated remote antenna units 716, andcan combine the various signals for transmission to respective remoteantenna units 716.

Although there is an equal number of base station sector controllers 712and remote antenna units 716, it will be apparent to a person ofordinary skill in the art that the number of remote antenna units 716may be different from the number of base station sector controllers 712,and the specific number of base station sector controllers 712 andremote antenna units 716 can vary according various implementations.

By way of an example and not by way of limitation, the base stationsector controller 712A may convey to the carrier separation filter 904Aa signal including downlink transmissions for a first carrier (e.g.,carrier 1) and for a second carrier (e.g., carrier 2). These downlinktransmissions are associated with a common sector identity (ID) of thebase station sector controller 712A. The carrier separation filter 904Afilters the signal to convey the downlink transmission for the firstcarrier to the carrier-specific RF connection matrix module 906 forcarrier 1 and the downlink transmission for the second carrier to thecarrier-specific RF connection matrix module 906 for carrier 2.

Generally speaking, and by way of example only, the carrier separationfilter 904A may receive a signal from the base station sector controller712A that includes downlink transmissions for a first carrier anddownlink transmissions for a second carrier. The carrier separationfilter 904A may filter the downlink transmissions communicated to thecarrier-specific RF connection matrix module 906 for carrier 1 toinclude only those downlink transmissions for the first carrier.Similarly, the carrier separation filter 904A may filter the downlinktransmissions communicated to the carrier-specific RF connection matrixmodule 906 for carrier 2 to include only those downlink transmissionsfor the second carrier. Similar operations may occur in the other basestation sector controllers 712B and 712C, and in the carrier separationfilters 904B and 904C.

The carrier-specific RF connection matrix module 906 for carrier 1 canroute received downlink transmissions to one or more remote antennaunits 716 for transmission on the first carrier. Similarly, thecarrier-specific RF connection matrix module 906 for carrier 2 can routereceived downlink transmissions to one or more remote antenna units 716for transmission on the second carrier. Simulcasting can be accomplishedby way of RF combining in the carrier-specific RF connection matrixmodules 906 in a manner similar to the RF combining described above withreference to the electrical portion of the RF connection matrix 704A inFIG. 8.

With the downlink transmissions in the respective carrier-specific RFconnection matrix modules 906 directed to their intended remote antennaunits 716, the downlink transmission signals from a plurality of thecarrier-specific RF connection matrix modules 906 can be combined fordownlink transmissions in the carrier combine filters 908 associatedwith each respective remote antenna unit 716. The combined signals canbe fed to the O/E interfaces so that corresponding optical signals aretransmitted over the respective optical cables 910 to the antenna units716 for de-simulcast and/or simulcast transmissions.

As depicted in FIG. 9, the RF connection matrix 704B can facilitatedifferent simulcast grouping per carrier by decomposing multicarrierbase station signals into separate per-carrier signals in the carrierseparation filters 904, and employing carrier-specific RF connectionmatrix modules 906 for each carrier. Moreover, in addition tofacilitating different simulcast groupings per carrier, the RFconnection matrix 704B can also facilitate simulcasting on the downlinkwhile using diversity antennas on the uplink. From a capacitystandpoint, it can be beneficial to exploit available diversity on theuplink, and the presented RF connection matrix 704B can provideincreased uplink capacity compared to conventional RF connection matrixconfigurations, which typically simulcast on the uplink. The separationof downlink and uplink multiplexing is not explicitly shown in FIG. 9,but will be readily understood from the diagram by a person of ordinaryskill in the art.

Turning to FIG. 10, a flow diagram is shown illustrating at least oneexample of a method operational on an RF connection matrix, such as theRF connection matrix 704B. Notably, although the following example onlyrefers to two different sector IDs and only two different carriers, itshould be understood that the specific number of sector IDs and/orcarriers can vary across any of a plurality of different examples. Withreference to FIGS. 9 and 10, a signal can be received at step 1002,where the signal is associated with a sector ID and includes downlinktransmissions for a plurality of carriers. For example, the RFconnection matrix 704B may receive one or more signals from a basestation sector controller 712, where the received signal is associatedwith a sector ID. For instance, the RF connection matrix 704B mayreceive a signal from the base station sector controller 712A associatedwith a first sector ID, and a signal from the base station sectorcontroller 712B associated with a second sector ID. The receivedsignal(s) (e.g., from each base station sector controller 712) mayinclude one or more downlink transmissions for transmission on a firstcarrier and one or more downlink transmissions for transmission on asecond carrier. The signal(s) from each base station sector controller712 may be received at a respective carrier separation filter 904.

At step 1004, downlink transmissions for a first carrier can be conveyedto a first carrier-specific RF connection matrix module 906. Forexample, the carrier separation filters 904 can filter out downlinktransmissions for any carriers other than the first carrier, and canconvey the resulting downlink transmissions for the first carrier to thecarrier-specific RF connection matrix module 906 for the first carrier.The carrier-specific RF connection matrix module 906 for the firstcarrier can accordingly receive downlink transmissions for one or moresector IDs associated with the first carrier.

Similarly, at step 1006, downlink transmissions for a second carrier canbe conveyed to a second carrier-specific RF connection matrix module906. For example, the carrier separation filters 904 can filter outdownlink transmissions for any carriers other than the second carrier,and can convey the resulting downlink transmissions for the secondcarrier to the carrier-specific RF connection matrix module 906 for thesecond carrier. The carrier-specific RF connection matrix module 906 forthe second carrier can accordingly receive downlink transmissions forone or more sector IDs associated with the second carrier.

At step 1008, the first carrier-specific RF connection matrix module 906can route the downlink transmissions for the first carrier to one ormore remote antenna units for transmission on the first carrier. Forexample, the carrier-specific RF connection matrix module 906 for thefirst carrier can route the downlink transmissions associated with eachsector ID for the first carrier to one or more remote antenna units 716.Routing for facilitating simulcasting by two or more remote antennaunits 716 can be accomplished by way of RF combining in a manner similarto the RF combining in the electrical portion of the RF connectionmatrix, as described above relating to the RF connection matrix 704A inFIG. 8.

Similarly, at step 1010, the second carrier-specific RF connectionmatrix module 906 can route the downlink transmissions for the secondcarrier to one or more remote antenna units for transmission on thesecond carrier. For example, the carrier-specific RF connection matrixmodule 906 for the second carrier can route the downlink transmissionsfor the second carrier to one or more remote antenna units 716. Routingfor facilitating simulcasting by two or more remote antenna units 716can be accomplished by way of RF combining in a manner similar to the RFcombining in the electrical portion of the RF connection matrix, asdescribed above relating to the RF connection matrix 704A in FIG. 8.

In at least some examples where both the first and secondcarrier-specific RF connection matrix modules 906 may route downlinktransmissions to one or more of the same remote antenna units 716. Insuch an example, the signals received from the two carrier-specific RFconnection matrix modules 906 can be combined into a signal by a carriercombine filter 908 prior to transmission by the respective remoteantenna units 716.

According to the forgoing examples, the RF connection matrix 704B canimplement one or more of the features described herein above withreference to FIGS. 2-5. For example, the carrier-specific RF connectionmatrix module 906 for the first carrier can simulcast a downlinktransmission on the first carrier over a first group of two or moreremote antenna units 716 employing a particular sector ID. Furthermore,the carrier-specific RF connection matrix module 906 for the secondcarrier can simulcast a downlink transmission on the second carrier overa second group of two or more remote antenna units employing the sectorID, wherein at least one remote antenna unit of the second group differsfrom the remote antenna units of the first group. In another example,the carrier-specific RF connection matrix modules 906 can simulcastdownlink transmissions over a plurality of remote antenna units 716,where at least one of the remote antenna units 716 is positioned so thata coverage area associated with the at least one remote antenna unit isnot adjacent to a coverage area associated with any of the other remoteantenna units of the plurality.

Referring back to FIG. 7, in order to adapt the RF connection matrix 704(e.g., RF connection matrix 704A in FIG. 8 and/or RF connection matrix704B in FIG. 9) to perform one or more of the features described hereinwith reference to FIGS. 2 and 4, the provisioning for a particularsimulcasting configuration can be highly complex, involving appropriateelectrical and/or optical connections to provide the downlink signal fora particular carrier to the proper remote antenna unit or units 716. Indeployments where more than one simulcasting configuration may bedesired, the RF connection matrix 704 (e.g., 704A, 704B) must beprovisioned to handle all possible simulcast and de-simulcast scenarios.Furthermore, in deployments where it is desired to dynamically changethe simulcasting and de-simulcasting configurations, the RF connectionmatrix 704 (e.g., 704A, 704B) will need to be provisioned with allpossible simulcast and de-simulcast scenarios in order for the RFconnection matrix 704 (e.g., 704A, 704B) to be able to dynamicallyadjust according to network traffic dynamics.

In some instances, the programming for the RF connection matrix 704(e.g., 704A, 704B) may interface with programming at the base stationcontroller 708, so that it can dynamically switch between varioussimulcasting and de-simulcasting configurations as needed to accommodatetraffic dynamics. Such an interface is depicted in FIG. 7 as interface720. In some instances, such an interface 720 between the RF connectionmatrix 704 (e.g., 704A, 704B) and the base station controller 708 may behandled manually by the operator.

In some instances, the remote antenna units 716 may be located atvarying distances from the RF connection matrix 704. Some remote antennaunits 716 may be located relatively close to the RF connection matrix704, while others are relatively distant therefrom. Accordingly, in asystem where multiple remote antenna units 716 are utilized forsimulcasting, the propagation delay for the downlink signal to arrive ata distant remote antenna unit 716 might be significantly longer than thepropagation delay for the same downlink signal to arrive at the remoteantenna unit 716 in closer proximity. During simulcast, it is intendedthat the same signal be transmitted by each remote antenna unit 716 atthe same or substantially the same time. However, if large differencesin the length of fiber optic cables (e.g., optic cables 806 in FIG. 8,optic cables 910 in FIG. 9) to each remote antenna unit 716 exist, itmay be difficult to synchronize the transmissions, and a delay spreadamong the simulcast antennas can go beyond the design specifications ofthe access terminals served by the simulcasting remote antenna units716. Accordingly, in at least some examples a suitable extra path lengthmay be added at the shorter paths, such as extra lengths of fiber,resulting in an equivalent path length for the simulcasted signals.

According to another feature of the present disclosure, a base stationsimulcast controller module may be implemented as part of a processingsystem 600 to facilitate simulcasting downlink transmissions accordingto one or more of the features described herein, such as those describedabove with reference to FIGS. 2-5. Such a base station simulcastcontroller module can enable base stations to simulcast downlinktransmissions without employing an RF connection matrix. The basestation simulcast controller module may be integrated as part of theprocessing system 600, such as by being integrated into the base stationin some examples. In other examples, the base station simulcastcontroller module may be implemented as its own processing system 600adapted to communicate with a plurality of base stations.

FIG. 11 is a block diagram illustrating select components of a basestation including an integrated base station simulcast controller moduleaccording to at least one example. That is, FIG. 11 illustrates anexample where a processing system is configured as a base stationincluding the base station simulcast controller module integrated aspart of the processing system. The illustrated example shows amacro-cell deployment in which multiple base station sectors may beimplemented in one form factor rack unit or channel card. Further, theillustrated example shows a single carrier architecture, wherein each ofthe base station sectors provides communication within the same carrierfrequency as one another. However, those of ordinary skill in the artwill understand that the modem block may be provisioned to providemultiple carriers, and may be provisioned to implement differingsimulcasting group configurations for different carriers as describedherein above.

In the illustrated system, a base station 1102 may be utilized alone orin conjunction with one or more additional different base stations thesame as base station 1102 or different from base station 1102 in awireless communication system to enable multiple access wirelesscommunication.

The base station 1102 may include a backhaul interface 1104 enablingbackhaul communication with one or more network nodes, such as a basestation controller 1106. The base station controller 1106, which maymanage general call processing functions, may additionally becommunicatively coupled to one or more additional base stations (notillustrated) over similar or different backhaul connections, and mayfurther be communicatively coupled to other network nodes suitable foruse in a wireless communication system, such as the Internet 1108.

Further, the base station 1102 may include a base station modem block1110 including a plurality of base station sector controllers 1112A,1112B, and 1112C and a base station simulcast controller module 1114.Such a base station simulcast controller module 1114 may also becharacterized as a transmit routing and delay correction entity.According to at least one example, the base station simulcast controllermodule 1114 may be implemented at least in part by a processing circuit.For instance, the processing circuit 602 of FIG. 6, alone or inconjunction with the simulcasting group distribution operations 614 inthe storage medium 606, can be employed to implement the base stationsimulcast controller module 1114.

The base station sector controllers 1112A, 1112B, and 1112C each includesufficient circuitry for transmitting a downlink and receiving an uplinkfor one sector in the wireless communication system, and may furthereach include circuitry for user scheduling, for determining a packettransmission format, and for waveform convolution. Here, the illustratedbase station modem block 1110 includes three base station sectorcontrollers 1112, but in various aspects of the present disclosure abase station modem block may include any suitable number of base stationsector controllers 1112.

Still further, the base station 1102 includes a plurality of basestation antenna ports 1116A, 1116B, and 1116C for interfacing withrespective remote antenna units 1118A, 1118B, and 1118C. Again, whilethe illustrated base station 1102 includes three base station antennaports, in various aspects of the present disclosure a base station 1102may include any suitable number of base station antenna ports, which mayor may not necessarily exactly correspond to the number of base stationsector controllers in the base station 1102.

According to various aspects of the present disclosure, the base stationsimulcast controller module 1114, included in the base station 1102,enables simulcasting and de-simulcasting utilizing the plurality ofremote antenna units 1118A, 1118B, and 1118C without the need for the RFconnection matrix. That is, the base station sector controllers 1112A,1112B, and 1112C each include a transmit interface and a receiveinterface. The transmit interface of each base station sector controller1112 is communicatively coupled to the base station simulcast controllermodule 1114, which processes the respective transmit signals asdescribed below for a particular simulcast configuration and accordinglyprovides the processed transmit signals to one or more respective basestation antenna ports 1116A, 1116B, and 1116C. In the illustratedexample, the remote antenna units 1118A and 1118B are employed as asimulcasting group for simulcasting downlink transmissions for basestation sector 1 on a particular carrier, while remote antenna unit1118C is employed for de-simulcast transmissions for base station sector2 on the same carrier. Group configurations for other carriers areomitted for clarity, but they may differ from the group configurationillustrated for the particular carrier.

On the other hand, the receive interface of each base station sectorcontroller 1112 can be communicatively coupled to a respective basestation antenna port 1116 without passing the received signals throughthe base station simulcast controller module 1114. In this way, aspectsof the present disclosure enable the base station modem block 1112 todecouple uplink transmissions from downlink transmissions so that uplinkcapacity can be improved. That is, in accordance with an aspect of thepresent disclosure, even when a plurality of the remote antenna units1118 are configured for simulcasting of downlink (forward link)transmissions, the reception of uplink (reverse link) transmissions arehandled separately so that the uplink transmissions can be eithersimulcasted or de-simulcasted independent of whether the downlinktransmissions are simulcasted or de-simulcasted. In this way,simulcasting of the downlink can improve the signal to interference andnoise ratio (SINR) for an access terminal served by the simulcasteddownlinks, while the uplink can additionally be improved with uplinkdiversity.

FIG. 12 is a block diagram detail view showing substantially the samearchitecture as illustrated in FIG. 11 for a DAS in accordance with anaspect of the present disclosure. Objects in FIG. 12 with the samenumber as objects in FIG. 11 are the same as those already described, sowill not be described in detail with respect to this figure. In theillustration, it can be seen that with this architecture, which replacesthe RF connection matrix 704 described above with reference to FIGS.7-9, connection from the base station 1102 to the remote antenna units1118 may be simplified. That is, the base station antenna ports 1116 ofone or more base stations 1102 may be controlled by the base stationcontroller 1106, which communicates with the respective base stations1102 over the backhaul interface 1104. While the base stations 1102 withtheir respective base station modem blocks 1112 are not illustrated, thebus illustrated by the backhaul interface 1104 can be taken to implythat any number of base stations 1102, such as the base station 1102illustrated in FIG. 11, are in communication with the base stationcontroller, where each respective base station 1102 includes a basestation simulcast controller module 1114, one or more base stationsector controllers 1112, and one or more base station antenna ports1116.

As seen in FIG. 12, the interface between respective base stationantenna ports 1116 and a central hub 1202 including corresponding O/Einterfaces is simplified, as compared to the examples utilizing the RFconnection matrix 704 depicted in FIGS. 8 and 9. For instance, asillustrated in FIG. 8, simulcasting might be accomplished by way of RFcombining 810. However, simulcasting can be accomplished by theabove-described features of the base station simulcast controller module1114, so RF combining 810 is not required. That is, only one RFconnection is required per downlink between each base station antennaport 1116 and O/E interface at the central hub 1202.

Additionally, the interface between respective O/E interfaces at thecentral hub 1202 and the remote antenna units 1118 is simplified, ascompared to the examples utilizing the RF connection matrix 704. Forinstance, as illustrated in FIG. 8, simulcasting with the RF connectionmatrix 704A might be accomplished by way of fiber combining 806C.However, as noted, simulcasting can be accomplished by theabove-described features of the base station simulcast controller module1114, so fiber combining 806C is not required. That is, only one opticfiber 1204 can be employed per downlink between the central hub 1202including the O/E interfaces and the remote antenna units 1118 includingthe E/O interfaces.

In a further aspect of the present disclosure, for each connectionbetween an O/E interface at the central hub 1002 and a respective E/Ointerface at a remote antenna unit 1118, the optic fiber 1204 mayinclude one single-mode fiber per downlink and one single-mode fiber peruplink. In this way, each link for sending uplink transmission signalsfrom a remote antenna unit 1118 to the hub 1202 may be de-simulcast,while each link for sending downlink transmission signals from the hub1202 to a remote antenna unit 1118 can be either simulcast orde-simulcast, as controlled by the base station simulcast controllermodule 1114.

In yet another aspect of the present disclosure, by virtue of a functionof the base station simulcast controller module 1114, the use of extralengths of fiber as discussed above to address the variable delays fordistant remote antenna units, can be eliminated. That is, here, thelengths of the optic fibers 1204 may still vary greatly, and thus,signals transmitted from a central hub 1202 may still exhibit disparatepropagation delays in accordance with the differences in length.However, the base station simulcast controller module 1114 may implementbuffering for delay correction so that remote antenna units 1118 whichare to participate in transmit simulcasting can be synchronized. Thatis, within the base station simulcast controller module 1114, delays maybe adjusted to improve simulcast performance by compensating forfiber-to-antenna delays. Here, delays may be cleanly controlled bysoftware and/or hardware in the base station simulcast controller module1114, for example, by digital buffering circuitry, to compensate forvariable propagation delays. Further, because the digital buffering maybe easily adjusted, corrections to delay amounts or changes in delayamounts when a remote antenna unit 1118 is relocated, for example, maybe made.

Employing the base station simulcast controller module 1114 tocompensate for variable propagation delays, instead of using extralengths of fiber, can provide substantial improvements to signal tointerference and noise ratios (SINR). For instance, it has beendiscovered that when the relative delay is controlled within one (1) totwo (2) chips, where one (1) chip is about 0.8 micro-seconds, then thesignal to interference and noise ratio grows linearly with the ratio oftotal received power from simulcasting antennas to total received powerfrom network. However, if the delay is left to the fiber, then there canbe significant loss from the optimal simulcasting signal to interferenceand noise ratio.

By including the base station simulcast controller module 1114 asdescribed above, the distribution (i.e., configuration) of simulcastinggroups can be readily modified to facilitate wireless transmissions fora given traffic scenario at a particular time. Further, the base station1102 may be capable of dynamically selecting between simulcasting andde-simulcasting distributions for downlink transmissions as needed inaccordance with one or more network traffic parameters. That is, at sometimes, based on at least one network traffic parameter (e.g., a trafficscenario, a network interference topology), improvements in coverage ofcertain locations may be desired, and thus, that location may be servedby simulcasting a downlink from several remote antenna units in thatarea. Further, at some times, improvements in capacity at certainlocations may be desired, and thus, that location may be served byde-simulcasting multiple downlinks from the remote antenna units in thatarea and/or by redistributing the simulcasting configuration to provideadditional sectors for that location. Here, because the change of therouting to the appropriate remote antenna unit 1118 is doneelectronically and internally to the base station 1102, there is nolonger a need for provisioning all possible simulcasting configurationsin advance, as was required when utilizing the RF connection matrix.That is, the base station simulcast controller module 1114 provides forimproved granularity in the selection of a simulcasting configuration inthat potentially every combination of simulcasting and de-simulcastingof the available remote antenna units 1118 may be implemented by asimple software command.

At least one feature of the present disclosure includes methodsoperational on a base station. FIG. 13 is a flow diagram illustrating atleast one example of a method operational on a base station. Referringto FIG. 13 together with FIG. 11, a base station 1102 can transmit, atstep 1302, downlink transmissions over a plurality of remote antennaunits 1118 (e.g., 1118A, 1118B, 1118C), where at least two of the remoteantenna units 1118 (e.g., 1118A and 1118B) are employed for simulcastingdownlink transmissions as a simulcasting group. The remote antenna unitscan be communicatively coupled to the antenna ports 1116 (e.g., 1116A,1116B, 1116C).

According to at least one example, the base station simulcast controllermodule 1114 can be adapted to transmit downlink transmissions over aplurality of remote antenna units 1118 communicatively coupled torespective base station antenna ports 1116. In some examples, the basestation simulcast controller module 1114 may be adapted to facilitatedownlink simulcasting by enabling electronic splitting of a transmitsignal from a base station sector controller 1112 to be provided to anynumber of the base station antenna ports 1116. The base stationsimulcast controller module 1114 can provide the electronically splittransmit signal to each of the remote antenna units 1116 employed forsimulcasting the transmit signal.

In some examples, the base station simulcast controller module 1114 canbe adapted to simulcast downlink transmissions according to the featuresdescribed herein with reference to FIGS. 2 and 3 above. For instance,the base station simulcast controller module 1114 can be adapted tosimulcast the downlink transmissions on a first carrier over a firstgroup of two or more remote antenna units 1118 employing a particularsector ID, while simulcasting downlink transmissions on a second carrierover a second group of two or more remote antenna units 1118 employingthe same sector ID. In such an example, at least one remote antenna unit1118 of the second group may differ from the remote antenna units 1118of the first group. The base station simulcast controller module 1114can further modify which remote antenna units 1118 are included in thefirst group and/or the second group, as described in more detail below.

In some examples, the base station simulcast controller module 1114 canbe adapted to simulcast downlink transmissions according to the featuresdescribed herein with reference to FIGS. 4 and 5 above. For instance,the base station simulcast controller module 1114 can be adapted tosimulcast the downlink transmissions over the plurality of remoteantenna units 1118 where at least one remote antenna unit 1118 ispositioned so that a coverage area associated with this at least oneremote antenna unit 1118 is not adjacent to a coverage area associatedwith any of the other remote antenna units 1118 of the plurality. Thebase station simulcast controller module 1114 can further modify whichremote antenna units 1118 are included in the simulcasting group, asdescribed in more detail below.

According to at least some examples, the base station 1102 can befurther adapted to receive uplink transmissions over the plurality ofremote antenna units that are de-simulcasted, even when downlinktransmissions are simulcasted. For example, the base station sectorcontrollers 1112A, 1112B, and 1112C can each include a transmitinterface and a receive interface. The transmit interface can becommunicatively coupled to the base station simulcast controller module1114 for facilitating simulcasted downlink transmissions, and thereceive interface can be communicatively coupled to a respective basestation antenna port 1116 without passing the received signals throughthe base station simulcast controller module 1114. Accordingly, evenwhen a plurality of the remote antenna units 1118 are configured forsimulcasting of downlink (forward link) transmissions, the reception ofuplink (reverse link) transmissions from the plurality of remote antennaunits 1118 are handled separately so that the uplink transmissions canbe de-simulcasted independent of whether the downlink transmissions aresimulcasted or de-simulcasted.

At step 1302, the base station 1102 can obtain one or more networktraffic parameters. For example, the base station simulcast controllermodule 1114 may be adapted to obtain the one or more network trafficparameters. In some instances, the base station 1102 can obtain the oneor more network traffic parameters by receiving a communication from thebase station controller 1106. As a result of the base station 1102 beingadapted to communicate with the base station controller 1106 by way ofthe backhaul interface 1104, knowledge of network traffic parameters,such as traffic usage and loading, can be readily exchanged to changethe simulcasting configuration when such a change would be beneficial.This can occur within carriers over time, or between carriers. In someexamples, the base station controller 1106 can determine a suitablegroup distribution (e.g., configuration) of some simulcasting remoteantenna units and some de-simulcasting remote antenna units, inaccordance with the traffic scenario, by communicating directly with thebase station 1102. For instance, the base station controller 1106 maymonitor traffic usage across the remote antenna units 1118, and mayutilize this information to optimally apply simulcasting andde-simulcasting in accordance with the traffic usage. In this example,the base station controller 1106 may provide network traffic parametersin the form of commands or instructions to the base station 1102. Thebase station 1102 (e.g., the base station simulcast controller module1114) can thereby readily change the simulcasting group distributions inaccordance with these instructions.

In other examples, the base station controller 1106 may provide thenetwork traffic parameters in the form of traffic information to thebase station simulcast controller module 1114 by way of the backhaulconnection 1104, and the base station simulcast controller module 1114may utilize this traffic information to make a determination regarding achange of the simulcasting configuration internally in accordance withthe received traffic information. That is, the base station simulcastcontroller module 1114 may be adapted to make a determination relatingto a change in the routing path of the transmit signal based on receivedinformation corresponding to traffic usage.

In response to the one or more network traffic parameters, the basestation 1102 can modify the simulcasting group configuration(s) at step1306. For example, the base station 1102 (e.g., the base stationsimulcast controller module 1114) can modify a simulcasting group toinclude at least one different remote antenna unit 1118 for simulcastingdownlink transmissions. That is, the base station simulcast controllermodule 1114 can remove and/or add one or more remote antenna units 1118included in a simulcasting group. In some examples, the base stationsimulcast controller module 1114 may be adapted to modify a simulcastinggroup by changing the routing path of a transmit signal received from abase station sector controller 1112 to transmit to a different remoteantenna port 1116 for simulcasting downlink transmissions.

As noted above, some configurations for a base station simulcastcontroller module include the base station simulcast controller moduleimplemented as its own processing system 600 adapted to communicate witha plurality of base stations. FIG. 14 is a block diagram illustratingselect components of a distributed antenna system (DAS) employing a basestation simulcast controller module 1402 implemented as a processingsystem adapted to communicate with a plurality of base stations.Configurations such as the one depicted by FIG. 14 may be suitable forimplementing a distributed antenna system (DAS) with a plurality of basestations employed as pico cells 1404 (e.g., 1404A, 1404B, and 1404C).That is, the base station simulcast controller module 1114 illustratedin FIG. 11 is integrated into a base station 1102 that may generally bereferred to as a macro cell, in which it is common to implement aplurality of base station sectors, e.g., by including the base stationsector controllers 1112. On the other hand, a pico cell 1404 (e.g.,1404A, 1404B, and 1404C) may typically include a controller for one ortwo base station sectors. In the illustration of FIG. 14, each pico cell1404A, 1404B, 1404C is shown as a single-sector base station, althoughaspects of the present disclosure can apply to multi-sector pico cells.

With this architecture, since the pico cells 1404 are separated, thearchitecture including a central base station simulcast controllermodule 1114 from FIG. 11 does not necessarily apply. Still, inaccordance with various aspects of the present disclosure, somecoordination for simulcasting of downlink transmissions through thebackhaul connecting the pico-cells 1404 together may be desired. Itshould be understood that when reference is made below to one or morefunctional aspects of the base station simulcast controller module 1402,such functional aspects can be implemented by a processing circuit ofthe base station simulcast controller module 1402, such as theprocessing circuit 602 implementing the simulcasting group distributionoperations 614 shown in FIG. 6.

In accordance with an aspect of the present disclosure, the architectureillustrated in FIG. 14 includes a base station simulcast controllermodule 1402, which is communicatively coupled to a plurality ofsingle-sector base stations 1404A, 1404B, and 1404C and to a basestation controller 1406. The base station simulcast controller module1402 can be communicatively coupled through a first backhaul interface1408 to the plurality of single-sector base stations 1404A, 1404B, and1404C, for example, utilizing a very low latency and low bandwidthconnection configured for simulcasting control. The base stationsimulcast controller module 1402 can be communicatively coupled to thebase station controller 1406 and to the plurality of base stations 1404by means of a communications interface, such as the communicationsinterface 604 described above with referent to FIG. 6.

The base station controller 1406 may also be communicatively coupledwith the respective base stations 1404 through a second backhaulinterface 1410. Here, the second backhaul interface 1410 may be a lowlatency connection for conventional communication of uplink and downlinkpackets between the base station controller 1406 and the base stations1404.

The base station simulcast controller module 1402 may be adapted toprovide the respective base stations 1404 over the first backhaulinterface 1408 with simulcasting control instructions or commands toimplement simulcasting or de-simulcasting, as needed, from therespective base stations 1404. The simulcasting control instructions maybe in accordance with one or more obtained traffic parameters (e.g.,traffic usage information provided by the base station controller 1406).Further, the base station simulcast controller module 1402 may directthe base station controller 1406 to send the same downlink packetsacross two or more base stations 1404 in simulcast, where the two ormore base station 1404 all use the same sector identity (ID) for thesimulcast. As illustrated, a first base station 1404A is configured forde-simulcasting the downlink transmission from its sector (e.g., sector1), and a second base station 1404B and third base station 1404C areconfigured to simulcast a downlink transmission for a different sector(e.g., sector 2). Of course, the base station simulcast controllermodule 1402 may configure the respective base stations 1404 to anysuitable simulcasting configuration in accordance with various aspectsof the present disclosure. Additionally, the depicted configuration maybe implemented for a one carrier, while a differentsimulcast/de-simulcast configuration may be implemented for a differentcarrier, such that different carriers employ different groupingconfigurations.

In a further aspect of the present disclosure, when a plurality of basestations such as the second base station 1404B and the third basestation 1404C are configured for simulcast, the base station simulcastcontroller module 1402 may select one of the plurality of simulcastingbase stations 1404B or 1404C to be a master, so that the other basestation(s) in simulcast will be slave(s). Here, the selected master basestation in the simulcast group may run a scheduler, and may select whichusers will be served. Further, the base station simulcast controllermodule 1402 may ensure that users selected by the master base stationare known to the slave base station(s), so that all simulcasting basestations properly format the same user packet selected for transmissionacross the simulcasting base stations.

In this architecture, since all base stations 1404 and the base stationsimulcast controller module 1402 are directly communicating with thebase station controller 1406, which manages general call processing, theknowledge of traffic usage and loading can be readily exchanged todynamically change the simulcasting configuration when needed.

As described herein above, the uplink signals may operate separatelyfrom each base station 1404, to improve the capacity for uplinktransmissions from access terminals to the respective base stations1404. Further, since the modem at each base station 1404 may operateacross multiple carriers, this architecture enables independentsimulcasting configurations to occur between carriers, as well asdynamically changing simulcasting configuration across carriers overtime. In general, the present architecture including the base stationsimulcast controller module 1402 can be employed for implementing any ofthe various simulcasting distributions described herein above withreference to FIGS. 2-5, except that one or more of the remote antennaunits in those examples can be implemented by base stations 1404 in thepresent example. That is, the base station simulcast controller module1402 can be adapted to select the simulcasting base stations 1404 toimplement any of the features and configurations described above withreference to FIGS. 2-5.

In yet a further aspect of the present disclosure, the architectureillustrated in FIG. 14 utilizes communication interfaces over therespective backhaul interfaces 1410 and 1408, such that RF-over-fiberconnections for coupling the base station 1404 to distant remote antennaunits are not needed. Thus, special circuitry to process differentialpropagation delays over variable-length optic fiber cables may not benecessary in this architecture. Nonetheless, due to differences indistance for the propagation of the backhaul signal over the secondbackhaul interface 1410, at least one of the base station simulcastcontroller module 1402 or the base station controller 1406 may beprovisioned to suitably handle variable delays so that the simulcastedsignals from the respective base stations 1404 are at leastsubstantially synchronized.

Further aspects of the present disclosure are related to methodsoperational for a base station simulcast controller module, such as thebase station simulcast controller module 1402. FIG. 15 is a flow diagramillustrating at least one example of such a method. Referring to FIGS.14 and 15, a base station simulcast controller module 1402 may send amessage to a base station controller to direct the base stationcontroller to send the same downlink packets across each of a pluralityof base stations for simulcast with a common (i.e., the same) sectoridentity (ID), at step 1502. For example, a processing circuit (e.g.,the processing circuit 602 implementing the simulcasting groupdistribution operations 614 shown in FIG. 6) can be adapted to generateand transmit the message to a base station controller 1406 to direct thebase station controller 1406. The transmitted message may also identifythe sector ID to be employed by the plurality of remotely deployed basestations.

According to various features, the processing circuit may be adapted toselect the plurality of base stations in accordance with the variousfeatures described above with reference to FIGS. 2-5. For example, theprocessing circuit may be adapted select the plurality of base stationsto include a first group of two or more base stations for simulcastingdownlink transmissions on a first carrier with a sector ID, and a secondgroup of two or more base stations for simulcasting downlinktransmissions on a second carrier with the same sector ID. At least onebase station of the second group can differ from the two or more basestations making up the first group. In another example, the processingcircuit can be adapted to select the plurality of base stations toinclude at least one base station that is located so that a coveragearea associated with that at least one base station is not adjacent to acoverage area associated with any of the other base stations of theplurality.

At step 1504, the base station simulcast controller module 1402 can sendone or more simulcasting control instructions to the plurality of basestations. The one or more simulcasting control instructions may beadapted for facilitating simulcasting from the plurality of basestations. In at least one example, the processing circuit (e.g., theprocessing circuit 602 implementing the simulcasting group distributionoperations 614 of FIG. 6) can be adapted to send the one or moresimulcasting control instructions to the plurality of base stations 1404over a backhaul interface 1408.

In some implementations, the base station simulcast controller module1402 may obtain one or more network traffic parameters, as indicated bystep 1506. For example, the processing circuit (e.g., the processingcircuit 602 implementing the simulcasting group distribution operations614 in FIG. 6) may obtain traffic parameters, such as a traffic scenarioor a network interference topology. The processing circuit may obtainsuch network traffic parameters from the base stations 1404, the basestation controller 1406, or a combination thereof.

At step 1508, the base station simulcast controller module 1402 canimplement or modify simulcasting at the plurality of base stations inresponse to the one or more traffic parameters. For instance, theprocessing circuit (e.g., the processing circuit 602 implementing thesimulcasting group distribution operations 614 in FIG. 6) may evaluatethe network traffic parameters and/or an instruction associated with thenetwork traffic parameters and responsively implement or modify asimulcasting configuration according to those traffic needs.

According to one or more other implementations, a method may alsoinclude steps for selecting a master base station and one or more slavebase stations, as described above, and/or synchronizing the downlinktransmissions from the plurality of base stations. Such additional oralternative steps can be carried out by the processing circuit (e.g.,the processing circuit 602 implementing the simulcasting groupdistribution operations 614 in FIG. 6).

One or more of the components, steps, features and/or functionsillustrated in FIGS. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14and/or 15 may be rearranged and/or combined into a single component,step, feature or function or embodied in several components, steps, orfunctions. Additional elements, components, steps, and/or functions mayalso be added without departing from the scope of the presentdisclosure. The apparatus, devices and/or components illustrated inFIGS. 1, 4, 6, 7, 8, 9, 11, 12 and/or 14 may be configured to performone or more of the methods, features, or steps described in FIGS. 2, 3,4, 5, 10, 13 and/or 15. The novel algorithms described herein may alsobe efficiently implemented in software and/or embedded in hardware.

Also, it is noted that at least some implementations have been describedas a process that is depicted as a flowchart, a flow diagram, astructure diagram, or a block diagram. Although a flowchart may describethe operations as a sequential process, many of the operations can beperformed in parallel or concurrently. In addition, the order of theoperations may be re-arranged. A process is terminated when itsoperations are completed. A process may correspond to a method, afunction, a procedure, a subroutine, a subprogram, etc. When a processcorresponds to a function, its termination corresponds to a return ofthe function to the calling function or the main function.

Those of skill in the art would further appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the embodiments disclosed herein may beimplemented as hardware, software, firmware, middleware, microcode, orany combination thereof. To clearly illustrate this interchangeability,various illustrative components, blocks, modules, circuits, and stepshave been described above generally in terms of their functionality.Whether such functionality is implemented as hardware or softwaredepends upon the particular application and design constraints imposedon the overall system.

The terms “machine-readable medium”, “computer-readable medium”, and/or“processor-readable medium” may include, but are not limited to portableor fixed storage devices, optical storage devices, and various othernon-transitory mediums capable of storing, containing or carryinginstruction(s) and/or data. Thus, the various methods described hereinmay be partially or fully implemented by instructions and/or data thatmay be stored in a “machine-readable medium”, “computer-readablemedium”, and/or “processor-readable medium” and executed by one or moreprocessors, machines and/or devices.

The various features of the embodiments described herein can beimplemented in different systems without departing from the scope of thedisclosure. It should be noted that the foregoing embodiments are merelyexamples and are not to be construed as limiting the disclosure. Thedescription of the embodiments is intended to be illustrative, and notto limit the scope of the claims. As such, the present teachings can bereadily applied to other types of apparatuses and many alternatives,modifications, and variations will be apparent to those skilled in theart.

What is claimed is:
 1. A distributed antenna system, comprising: aplurality of remote antenna units spatially separated from one another;a first group of remote antenna units selected from the plurality ofremote antenna units, the first group adapted to simulcast downlinktransmissions with a sector identity (ID) on a first carrier; and asecond group of remote antenna units selected from the plurality ofremote antenna units, wherein at least one remote antenna unit of thesecond group differs from the remote antenna units of the first group,the second group adapted to simulcast downlink transmission with thesector ID on a second carrier different from the first carrier.
 2. Thedistributed antenna system of claim 1, wherein the plurality of remoteantenna units are communicatively coupled with at least one basestation.
 3. The distributed antenna system of claim 2, wherein the basestation is coupled with an RF connection matrix for facilitating thesimulcast downlink transmissions for the first group and the secondgroup.
 4. The distributed antenna system of claim 3, wherein the RFconnection matrix comprises: a first carrier-specific RF connectionmatrix module adapted to route a first downlink transmission to one ormore remote antenna units for transmission on a first carrier; and asecond carrier-specific RF connection matrix module adapted to route asecond downlink transmission to one or more remote antenna units fortransmission on a second carrier.
 5. The distributed antenna system ofclaim 2, wherein the base station includes an integrated base stationsimulcast controller module for facilitating the simulcast downlinktransmissions for the first group and the second group.
 6. Thedistributed antenna system of claim 2, wherein the plurality of remoteantenna units are each communicatively coupled to a respective basestation, and each respective base station is coupled with a base stationsimulcast controller module apparatus for facilitating the simulcastdownlink transmissions for the first group and the second group.
 7. Thedistributed antenna system of claim 1, wherein at least one remoteantenna unit included in the first group is also included in the secondgroup of remote antenna units, and is adapted to simulcast downlinktransmissions on both the first carrier with the first group and on thesecond carrier with the second group.
 8. A method for wirelesscommunication, comprising: simulcasting downlink transmissions on afirst carrier with a first group of two or more remote antenna unitsemploying a sector identity (ID); and simulcasting downlinktransmissions on a second carrier with a second group of two or moreremote antenna units employing the sector ID, wherein at least oneremote antenna unit of the second group differs from the remote antennaunits of the first group.
 9. The method of claim 8, wherein the firstgroup includes at least one remote antenna unit that is also included inthe second group of two or more remote antenna units.
 10. The method ofclaim 8, further comprising: changing at least one remote antenna unitfor the first group, the second group, or both the first group and thesecond group in response to at least one network traffic parameter. 11.A distributed antenna system, comprising: means for simulcastingdownlink transmissions on a first carrier with a first group of two ormore remote antenna units employing a sector identity (ID); and meansfor simulcasting downlink transmissions on a second carrier with asecond group of two or more remote antenna units employing the sectorID, wherein at least one remote antenna unit of the second group differsfrom the remote antenna units of the first group.
 12. The distributedantenna system of claim 11, further comprising: means for changing atleast one remote antenna unit for the first group, the second group, orboth the first group and the second group in response to at least onenetwork traffic parameter.
 13. A computer program product comprising: aprocessor-readable medium comprising instructions for: simulcastingdownlink transmissions on a first carrier with a first group of two ormore remote antenna units employing a sector identity (ID); andsimulcasting downlink transmissions on a second carrier with a secondgroup of two or more remote antenna units employing the sector ID,wherein at least one remote antenna unit of the second group differsfrom the remote antenna units of the first group.
 14. The computerprogram product of claim 13, wherein the first group includes at leastone remote antenna unit that is also included in the second group of twoor more remote antenna units.
 15. The computer program product of claim13, wherein the processor-readable medium further comprises instructionsfor: changing at least one remote antenna unit for the first group, thesecond group, or both the first group and the second group in responseto at least one network traffic parameter.
 16. A distributed antennasystem, comprising: a plurality of remote antenna units spatiallyseparated from one another, wherein two or more remote antenna unitswith respective coverage areas that are non-adjacent to one another areadapted to simulcast downlink transmissions.
 17. The distributed antennasystem of claim 16, wherein each of the two or more remote antenna unitsadapted to simulcast downlink transmission are separated from oneanother with at least one other remote antenna unit that does notsimulcast with the two or more remote antenna units.
 18. The distributedantenna system of claim 16, wherein the plurality of remote antennaunits are communicatively coupled with an RF connection matrix forfacilitating the simulcast downlink transmissions for the two or moreremote antenna units.
 19. The distributed antenna system of claim 18,wherein the RF connection matrix comprises: a first carrier-specific RFconnection matrix module adapted to route a first downlink transmissionto one or more remote antenna units for transmission on a first carrier;and a second carrier-specific RF connection matrix module adapted toroute a second downlink transmission to one or more remote antenna unitsfor transmission on a second carrier.
 20. The distributed antenna systemof claim 16, wherein the plurality of remote antenna units arecommunicatively coupled with a base station including an integrated basestation simulcast controller module for facilitating the simulcastdownlink transmissions for the two or more remote antenna units.
 21. Thedistributed antenna system of claim 16, wherein each of the plurality ofremote antenna units is communicatively coupled with a respective basestation, and each respective base station is coupled with an externalbase station simulcast controller module apparatus for facilitating thesimulcast downlink transmissions for the two or more remote antennaunits.
 22. A method for wireless communication comprising: simulcastingdownlink transmissions with a first remote antenna unit; andsimulcasting the downlink transmissions with a second remote antennaunit, the first remote antenna unit and the second remote antenna unitforming a simulcasting group, wherein the second remote antenna unit ispositioned so that a coverage area associated with the second remoteantenna unit is not adjacent to a coverage area associated with thefirst remote antenna unit.
 23. The method of claim 22, furthercomprising: adding at least one additional remote antenna unit to thesimulcasting group in response to at least one network trafficparameter.
 24. The method of claim 22, wherein the simulcasting groupincludes one or more other remote antenna units, and further comprising:removing at least one remote antenna from the simulcasting group inresponse to at least one network traffic parameter.
 25. A distributedantenna system comprising: means for simulcasting downlink transmissionswith a first remote antenna unit; and means for simulcasting thedownlink transmissions with a second remote antenna unit, the firstremote antenna unit and the second remote antenna unit forming asimulcasting group, wherein the second remote antenna unit is positionedso that a coverage area associated with the second remote antenna unitis not adjacent to a coverage area associated with the first remoteantenna unit.
 26. A computer program product comprising: aprocessor-readable medium comprising instructions for: simulcastingdownlink transmissions with a plurality of remote antenna units, whereinat least one of the remote antenna units is positioned so that acoverage area associated with the at least one remote antenna unit isnot adjacent to a coverage area associated with any of the other remoteantenna units of the plurality.